1. Field of the Invention
The present invention relates to a nonaqueous electrolyte battery and, more particularly, to a nonaqueous electrolyte battery in which a self-discharge is suppressed and a storage property is improved.
This application claims priority of Japanese Patent Application No. 2002-024243, filed on Jan. 31, 2002, the entirety of which is incorporated by reference herein.
2. Description of the Related Art
With the progress of recent electronic technology, electronic devices such as a video camera with video tape recorders, portable telephones, lap top computers, etc. have been developed. Then, as portable power sources employed for these electronic devices, the development of compact and light secondary batteries having high energy density has been eagerly demanded.
As secondary batteries which satisfy such a demand, nonaqueous electrolyte secondary batteries using light metals, such as lithium (Li), sodium (Na), aluminum (Al), and the like, as negative active materials have been getting attention. These nonaqueous electrolyte secondary batteries, theoretically, can generate a higher voltage and have a higher energy density than those of aqueous, electrolyte secondary batteries. Nonaqueous electrolyte secondary batteries that are charged with and discharge lithium ions (Li+) through nonaqueous electrolyte solution have been progressively and vigorously studied and developed as batteries which can realize a high output and a high energy density.
The above-described lithium secondary battery comprises an anode composed of, for instance, lithium, lithium alloy or a compound of lithium and a carbonaceous material and capable of reversibly doping with and dedoping from lithium ions, a cathode and a nonaqueous electrolyte interposed between the cathode and the anode.
However, the battery using the nonaqueous electrolyte solution obtained by dissolving an electrolyte salt in a nonaqueous solvent as the nonaqueous electrolyte is inconveniently large in its self-discharge and inferior in its storage characteristics.